What is the Relationship between Flow and Turbidity in the
Red Cedar River?
Turbidity and flow are important river characteristics to know. Turbidity, the
concentration of particles
μm in size that are suspended in the water, tells us
about the water clarity. Flow tells us how much water is moving through the water
system, in this case the Red Cedar River. By looking at the two characteristics
together, a person can see how different amounts of flow changes the amount of
turbidity in the river.
Knowing the changes in the turbidity and flow allows us to
prepare for things like sediment build up when the flow is low or the picking up of
larger particles when the flow is high. If there is a dam or reservoir, this can be a
major issue. If the sediment builds up a lot, the reservoir can’t hold as much
drinking water which, in some places, causes major problems. If the dam is a small
one, and sediment keeps building up and blocking off more and more water, the
dam may eventually break causing flooding. On the reverse side, if there is a lot of
flow and the turbidity is high, with large particles such as rocks, structures like
small dams may fail which would also cause flooding.
So as you can see,
understanding the amount of particles in a river system and how its related to flow
is relatively important.
My hypothesis for this experiment is that with more flow there is more
turbidity. I think this because as the water is moving faster, I think it will pick up
more sediment from the bottom and edges of the river that it normally would not. In
doing this, there would be more particles suspended in the water and therefore, by
definition, a higher turbidity in the river.
For this experiment, the supplies needed are a bucket capable of collecting at
least one liter of water, a rope approximately two meters long, a weight (to attach to
the bucket in order to sink the bucket and collect water), a filtering manifold,
graduated cylinders, a supply of filters that will retain particles
μm big, plastic
dishes for drying and storing the filters, an oven and desiccator to dry the filters
and a precise balance scale. For this experiment, 9 turbidity samples (from 9
different days) are needed.